Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1065 insertions, 0 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
new file mode 100644
index 000000000..b9e9562f5
--- /dev/null
+++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -0,0 +1,1065 @@
+/*
+ * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
+ * Copyright (c) 2004 Voltaire, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/moduleparam.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <linux/igmp.h>
+#include <linux/inetdevice.h>
+#include <linux/delay.h>
+#include <linux/completion.h>
+#include <linux/slab.h>
+
+#include <net/dst.h>
+
+#include "ipoib.h"
+
+#ifdef CONFIG_INFINIBAND_IPOIB_DEBUG
+static int mcast_debug_level;
+
+module_param(mcast_debug_level, int, 0644);
+MODULE_PARM_DESC(mcast_debug_level,
+		 "Enable multicast debug tracing if > 0");
+#endif
+
+struct ipoib_mcast_iter {
+	struct net_device *dev;
+	union ib_gid       mgid;
+	unsigned long      created;
+	unsigned int       queuelen;
+	unsigned int       complete;
+	unsigned int       send_only;
+};
+
+/* join state that allows creating mcg with sendonly member request */
+#define SENDONLY_FULLMEMBER_JOIN	8
+
+/*
+ * This should be called with the priv->lock held
+ */
+static void __ipoib_mcast_schedule_join_thread(struct ipoib_dev_priv *priv,
+					       struct ipoib_mcast *mcast,
+					       bool delay)
+{
+	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags))
+		return;
+
+	/*
+	 * We will be scheduling *something*, so cancel whatever is
+	 * currently scheduled first
+	 */
+	cancel_delayed_work(&priv->mcast_task);
+	if (mcast && delay) {
+		/*
+		 * We had a failure and want to schedule a retry later
+		 */
+		mcast->backoff *= 2;
+		if (mcast->backoff > IPOIB_MAX_BACKOFF_SECONDS)
+			mcast->backoff = IPOIB_MAX_BACKOFF_SECONDS;
+		mcast->delay_until = jiffies + (mcast->backoff * HZ);
+		/*
+		 * Mark this mcast for its delay, but restart the
+		 * task immediately.  The join task will make sure to
+		 * clear out all entries without delays, and then
+		 * schedule itself to run again when the earliest
+		 * delay expires
+		 */
+		queue_delayed_work(priv->wq, &priv->mcast_task, 0);
+	} else if (delay) {
+		/*
+		 * Special case of retrying after a failure to
+		 * allocate the broadcast multicast group, wait
+		 * 1 second and try again
+		 */
+		queue_delayed_work(priv->wq, &priv->mcast_task, HZ);
+	} else
+		queue_delayed_work(priv->wq, &priv->mcast_task, 0);
+}
+
+static void ipoib_mcast_free(struct ipoib_mcast *mcast)
+{
+	struct net_device *dev = mcast->dev;
+	int tx_dropped = 0;
+
+	ipoib_dbg_mcast(ipoib_priv(dev), "deleting multicast group %pI6\n",
+			mcast->mcmember.mgid.raw);
+
+	/* remove all neigh connected to this mcast */
+	ipoib_del_neighs_by_gid(dev, mcast->mcmember.mgid.raw);
+
+	if (mcast->ah)
+		ipoib_put_ah(mcast->ah);
+
+	while (!skb_queue_empty(&mcast->pkt_queue)) {
+		++tx_dropped;
+		dev_kfree_skb_any(skb_dequeue(&mcast->pkt_queue));
+	}
+
+	netif_tx_lock_bh(dev);
+	dev->stats.tx_dropped += tx_dropped;
+	netif_tx_unlock_bh(dev);
+
+	kfree(mcast);
+}
+
+static struct ipoib_mcast *ipoib_mcast_alloc(struct net_device *dev,
+					     int can_sleep)
+{
+	struct ipoib_mcast *mcast;
+
+	mcast = kzalloc(sizeof(*mcast), can_sleep ? GFP_KERNEL : GFP_ATOMIC);
+	if (!mcast)
+		return NULL;
+
+	mcast->dev = dev;
+	mcast->created = jiffies;
+	mcast->delay_until = jiffies;
+	mcast->backoff = 1;
+
+	INIT_LIST_HEAD(&mcast->list);
+	INIT_LIST_HEAD(&mcast->neigh_list);
+	skb_queue_head_init(&mcast->pkt_queue);
+
+	return mcast;
+}
+
+static struct ipoib_mcast *__ipoib_mcast_find(struct net_device *dev, void *mgid)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	struct rb_node *n = priv->multicast_tree.rb_node;
+
+	while (n) {
+		struct ipoib_mcast *mcast;
+		int ret;
+
+		mcast = rb_entry(n, struct ipoib_mcast, rb_node);
+
+		ret = memcmp(mgid, mcast->mcmember.mgid.raw,
+			     sizeof (union ib_gid));
+		if (ret < 0)
+			n = n->rb_left;
+		else if (ret > 0)
+			n = n->rb_right;
+		else
+			return mcast;
+	}
+
+	return NULL;
+}
+
+static int __ipoib_mcast_add(struct net_device *dev, struct ipoib_mcast *mcast)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	struct rb_node **n = &priv->multicast_tree.rb_node, *pn = NULL;
+
+	while (*n) {
+		struct ipoib_mcast *tmcast;
+		int ret;
+
+		pn = *n;
+		tmcast = rb_entry(pn, struct ipoib_mcast, rb_node);
+
+		ret = memcmp(mcast->mcmember.mgid.raw, tmcast->mcmember.mgid.raw,
+			     sizeof (union ib_gid));
+		if (ret < 0)
+			n = &pn->rb_left;
+		else if (ret > 0)
+			n = &pn->rb_right;
+		else
+			return -EEXIST;
+	}
+
+	rb_link_node(&mcast->rb_node, pn, n);
+	rb_insert_color(&mcast->rb_node, &priv->multicast_tree);
+
+	return 0;
+}
+
+static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
+				   struct ib_sa_mcmember_rec *mcmember)
+{
+	struct net_device *dev = mcast->dev;
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	struct rdma_netdev *rn = netdev_priv(dev);
+	struct ipoib_ah *ah;
+	struct rdma_ah_attr av;
+	int ret;
+	int set_qkey = 0;
+
+	mcast->mcmember = *mcmember;
+
+	/* Set the multicast MTU and cached Q_Key before we attach if it's
+	 * the broadcast group.
+	 */
+	if (!memcmp(mcast->mcmember.mgid.raw, priv->dev->broadcast + 4,
+		    sizeof (union ib_gid))) {
+		spin_lock_irq(&priv->lock);
+		if (!priv->broadcast) {
+			spin_unlock_irq(&priv->lock);
+			return -EAGAIN;
+		}
+		/*update priv member according to the new mcast*/
+		priv->broadcast->mcmember.qkey = mcmember->qkey;
+		priv->broadcast->mcmember.mtu = mcmember->mtu;
+		priv->broadcast->mcmember.traffic_class = mcmember->traffic_class;
+		priv->broadcast->mcmember.rate = mcmember->rate;
+		priv->broadcast->mcmember.sl = mcmember->sl;
+		priv->broadcast->mcmember.flow_label = mcmember->flow_label;
+		priv->broadcast->mcmember.hop_limit = mcmember->hop_limit;
+		/* assume if the admin and the mcast are the same both can be changed */
+		if (priv->mcast_mtu == priv->admin_mtu)
+			priv->admin_mtu =
+			priv->mcast_mtu =
+			IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu));
+		else
+			priv->mcast_mtu =
+			IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu));
+
+		priv->qkey = be32_to_cpu(priv->broadcast->mcmember.qkey);
+		spin_unlock_irq(&priv->lock);
+		priv->tx_wr.remote_qkey = priv->qkey;
+		set_qkey = 1;
+	}
+
+	if (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
+		if (test_and_set_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags)) {
+			ipoib_warn(priv, "multicast group %pI6 already attached\n",
+				   mcast->mcmember.mgid.raw);
+
+			return 0;
+		}
+
+		ret = rn->attach_mcast(dev, priv->ca, &mcast->mcmember.mgid,
+				       be16_to_cpu(mcast->mcmember.mlid),
+				       set_qkey, priv->qkey);
+		if (ret < 0) {
+			ipoib_warn(priv, "couldn't attach QP to multicast group %pI6\n",
+				   mcast->mcmember.mgid.raw);
+
+			clear_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags);
+			return ret;
+		}
+	}
+
+	memset(&av, 0, sizeof(av));
+	av.type = rdma_ah_find_type(priv->ca, priv->port);
+	rdma_ah_set_dlid(&av, be16_to_cpu(mcast->mcmember.mlid)),
+	rdma_ah_set_port_num(&av, priv->port);
+	rdma_ah_set_sl(&av, mcast->mcmember.sl);
+	rdma_ah_set_static_rate(&av, mcast->mcmember.rate);
+
+	rdma_ah_set_grh(&av, &mcast->mcmember.mgid,
+			be32_to_cpu(mcast->mcmember.flow_label),
+			0, mcast->mcmember.hop_limit,
+			mcast->mcmember.traffic_class);
+
+	ah = ipoib_create_ah(dev, priv->pd, &av);
+	if (IS_ERR(ah)) {
+		ipoib_warn(priv, "ib_address_create failed %ld\n",
+			   -PTR_ERR(ah));
+		/* use original error */
+		return PTR_ERR(ah);
+	}
+	spin_lock_irq(&priv->lock);
+	mcast->ah = ah;
+	spin_unlock_irq(&priv->lock);
+
+	ipoib_dbg_mcast(priv, "MGID %pI6 AV %p, LID 0x%04x, SL %d\n",
+			mcast->mcmember.mgid.raw,
+			mcast->ah->ah,
+			be16_to_cpu(mcast->mcmember.mlid),
+			mcast->mcmember.sl);
+
+	/* actually send any queued packets */
+	netif_tx_lock_bh(dev);
+	while (!skb_queue_empty(&mcast->pkt_queue)) {
+		struct sk_buff *skb = skb_dequeue(&mcast->pkt_queue);
+
+		netif_tx_unlock_bh(dev);
+
+		skb->dev = dev;
+
+		ret = dev_queue_xmit(skb);
+		if (ret)
+			ipoib_warn(priv, "%s:dev_queue_xmit failed to re-queue packet, ret:%d\n",
+				   __func__, ret);
+		netif_tx_lock_bh(dev);
+	}
+	netif_tx_unlock_bh(dev);
+
+	return 0;
+}
+
+void ipoib_mcast_carrier_on_task(struct work_struct *work)
+{
+	struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
+						   carrier_on_task);
+	struct ib_port_attr attr;
+
+	if (ib_query_port(priv->ca, priv->port, &attr) ||
+	    attr.state != IB_PORT_ACTIVE) {
+		ipoib_dbg(priv, "Keeping carrier off until IB port is active\n");
+		return;
+	}
+	/*
+	 * Check if can send sendonly MCG's with sendonly-fullmember join state.
+	 * It done here after the successfully join to the broadcast group,
+	 * because the broadcast group must always be joined first and is always
+	 * re-joined if the SM changes substantially.
+	 */
+	priv->sm_fullmember_sendonly_support =
+		ib_sa_sendonly_fullmem_support(&ipoib_sa_client,
+					       priv->ca, priv->port);
+	/*
+	 * Take rtnl_lock to avoid racing with ipoib_stop() and
+	 * turning the carrier back on while a device is being
+	 * removed.  However, ipoib_stop() will attempt to flush
+	 * the workqueue while holding the rtnl lock, so loop
+	 * on trylock until either we get the lock or we see
+	 * FLAG_OPER_UP go away as that signals that we are bailing
+	 * and can safely ignore the carrier on work.
+	 */
+	while (!rtnl_trylock()) {
+		if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags))
+			return;
+		else
+			msleep(20);
+	}
+	if (!ipoib_cm_admin_enabled(priv->dev))
+		dev_set_mtu(priv->dev, min(priv->mcast_mtu, priv->admin_mtu));
+	netif_carrier_on(priv->dev);
+	rtnl_unlock();
+}
+
+static int ipoib_mcast_join_complete(int status,
+				     struct ib_sa_multicast *multicast)
+{
+	struct ipoib_mcast *mcast = multicast->context;
+	struct net_device *dev = mcast->dev;
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+
+	ipoib_dbg_mcast(priv, "%sjoin completion for %pI6 (status %d)\n",
+			test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) ?
+			"sendonly " : "",
+			mcast->mcmember.mgid.raw, status);
+
+	/* We trap for port events ourselves. */
+	if (status == -ENETRESET) {
+		status = 0;
+		goto out;
+	}
+
+	if (!status)
+		status = ipoib_mcast_join_finish(mcast, &multicast->rec);
+
+	if (!status) {
+		mcast->backoff = 1;
+		mcast->delay_until = jiffies;
+
+		/*
+		 * Defer carrier on work to priv->wq to avoid a
+		 * deadlock on rtnl_lock here.  Requeue our multicast
+		 * work too, which will end up happening right after
+		 * our carrier on task work and will allow us to
+		 * send out all of the non-broadcast joins
+		 */
+		if (mcast == priv->broadcast) {
+			spin_lock_irq(&priv->lock);
+			queue_work(priv->wq, &priv->carrier_on_task);
+			__ipoib_mcast_schedule_join_thread(priv, NULL, 0);
+			goto out_locked;
+		}
+	} else {
+		bool silent_fail =
+		    test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) &&
+		    status == -EINVAL;
+
+		if (mcast->logcount < 20) {
+			if (status == -ETIMEDOUT || status == -EAGAIN ||
+			    silent_fail) {
+				ipoib_dbg_mcast(priv, "%smulticast join failed for %pI6, status %d\n",
+						test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) ? "sendonly " : "",
+						mcast->mcmember.mgid.raw, status);
+			} else {
+				ipoib_warn(priv, "%smulticast join failed for %pI6, status %d\n",
+						test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) ? "sendonly " : "",
+					   mcast->mcmember.mgid.raw, status);
+			}
+
+			if (!silent_fail)
+				mcast->logcount++;
+		}
+
+		if (test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) &&
+		    mcast->backoff >= 2) {
+			/*
+			 * We only retry sendonly joins once before we drop
+			 * the packet and quit trying to deal with the
+			 * group.  However, we leave the group in the
+			 * mcast list as an unjoined group.  If we want to
+			 * try joining again, we simply queue up a packet
+			 * and restart the join thread.  The empty queue
+			 * is why the join thread ignores this group.
+			 */
+			mcast->backoff = 1;
+			netif_tx_lock_bh(dev);
+			while (!skb_queue_empty(&mcast->pkt_queue)) {
+				++dev->stats.tx_dropped;
+				dev_kfree_skb_any(skb_dequeue(&mcast->pkt_queue));
+			}
+			netif_tx_unlock_bh(dev);
+		} else {
+			spin_lock_irq(&priv->lock);
+			/* Requeue this join task with a backoff delay */
+			__ipoib_mcast_schedule_join_thread(priv, mcast, 1);
+			goto out_locked;
+		}
+	}
+out:
+	spin_lock_irq(&priv->lock);
+out_locked:
+	/*
+	 * Make sure to set mcast->mc before we clear the busy flag to avoid
+	 * racing with code that checks for BUSY before checking mcast->mc
+	 */
+	if (status)
+		mcast->mc = NULL;
+	else
+		mcast->mc = multicast;
+	clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
+	spin_unlock_irq(&priv->lock);
+	complete(&mcast->done);
+
+	return status;
+}
+
+/*
+ * Caller must hold 'priv->lock'
+ */
+static int ipoib_mcast_join(struct net_device *dev, struct ipoib_mcast *mcast)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	struct ib_sa_multicast *multicast;
+	struct ib_sa_mcmember_rec rec = {
+		.join_state = 1
+	};
+	ib_sa_comp_mask comp_mask;
+	int ret = 0;
+
+	if (!priv->broadcast ||
+	    !test_bit(IPOIB_FLAG_OPER_UP, &priv->flags))
+		return -EINVAL;
+
+	init_completion(&mcast->done);
+	set_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
+
+	ipoib_dbg_mcast(priv, "joining MGID %pI6\n", mcast->mcmember.mgid.raw);
+
+	rec.mgid     = mcast->mcmember.mgid;
+	rec.port_gid = priv->local_gid;
+	rec.pkey     = cpu_to_be16(priv->pkey);
+
+	comp_mask =
+		IB_SA_MCMEMBER_REC_MGID		|
+		IB_SA_MCMEMBER_REC_PORT_GID	|
+		IB_SA_MCMEMBER_REC_PKEY		|
+		IB_SA_MCMEMBER_REC_JOIN_STATE;
+
+	if (mcast != priv->broadcast) {
+		/*
+		 * RFC 4391:
+		 *  The MGID MUST use the same P_Key, Q_Key, SL, MTU,
+		 *  and HopLimit as those used in the broadcast-GID.  The rest
+		 *  of attributes SHOULD follow the values used in the
+		 *  broadcast-GID as well.
+		 */
+		comp_mask |=
+			IB_SA_MCMEMBER_REC_QKEY			|
+			IB_SA_MCMEMBER_REC_MTU_SELECTOR		|
+			IB_SA_MCMEMBER_REC_MTU			|
+			IB_SA_MCMEMBER_REC_TRAFFIC_CLASS	|
+			IB_SA_MCMEMBER_REC_RATE_SELECTOR	|
+			IB_SA_MCMEMBER_REC_RATE			|
+			IB_SA_MCMEMBER_REC_SL			|
+			IB_SA_MCMEMBER_REC_FLOW_LABEL		|
+			IB_SA_MCMEMBER_REC_HOP_LIMIT;
+
+		rec.qkey	  = priv->broadcast->mcmember.qkey;
+		rec.mtu_selector  = IB_SA_EQ;
+		rec.mtu		  = priv->broadcast->mcmember.mtu;
+		rec.traffic_class = priv->broadcast->mcmember.traffic_class;
+		rec.rate_selector = IB_SA_EQ;
+		rec.rate	  = priv->broadcast->mcmember.rate;
+		rec.sl		  = priv->broadcast->mcmember.sl;
+		rec.flow_label	  = priv->broadcast->mcmember.flow_label;
+		rec.hop_limit	  = priv->broadcast->mcmember.hop_limit;
+
+		/*
+		 * Send-only IB Multicast joins work at the core IB layer but
+		 * require specific SM support.
+		 * We can use such joins here only if the current SM supports that feature.
+		 * However, if not, we emulate an Ethernet multicast send,
+		 * which does not require a multicast subscription and will
+		 * still send properly. The most appropriate thing to
+		 * do is to create the group if it doesn't exist as that
+		 * most closely emulates the behavior, from a user space
+		 * application perspective, of Ethernet multicast operation.
+		 */
+		if (test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) &&
+		    priv->sm_fullmember_sendonly_support)
+			/* SM supports sendonly-fullmember, otherwise fallback to full-member */
+			rec.join_state = SENDONLY_FULLMEMBER_JOIN;
+	}
+	spin_unlock_irq(&priv->lock);
+
+	multicast = ib_sa_join_multicast(&ipoib_sa_client, priv->ca, priv->port,
+					 &rec, comp_mask, GFP_KERNEL,
+					 ipoib_mcast_join_complete, mcast);
+	spin_lock_irq(&priv->lock);
+	if (IS_ERR(multicast)) {
+		ret = PTR_ERR(multicast);
+		ipoib_warn(priv, "ib_sa_join_multicast failed, status %d\n", ret);
+		/* Requeue this join task with a backoff delay */
+		__ipoib_mcast_schedule_join_thread(priv, mcast, 1);
+		clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
+		spin_unlock_irq(&priv->lock);
+		complete(&mcast->done);
+		spin_lock_irq(&priv->lock);
+	}
+	return 0;
+}
+
+void ipoib_mcast_join_task(struct work_struct *work)
+{
+	struct ipoib_dev_priv *priv =
+		container_of(work, struct ipoib_dev_priv, mcast_task.work);
+	struct net_device *dev = priv->dev;
+	struct ib_port_attr port_attr;
+	unsigned long delay_until = 0;
+	struct ipoib_mcast *mcast = NULL;
+
+	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags))
+		return;
+
+	if (ib_query_port(priv->ca, priv->port, &port_attr)) {
+		ipoib_dbg(priv, "ib_query_port() failed\n");
+		return;
+	}
+	if (port_attr.state != IB_PORT_ACTIVE) {
+		ipoib_dbg(priv, "port state is not ACTIVE (state = %d) suspending join task\n",
+			  port_attr.state);
+		return;
+	}
+	priv->local_lid = port_attr.lid;
+	netif_addr_lock_bh(dev);
+
+	if (!test_bit(IPOIB_FLAG_DEV_ADDR_SET, &priv->flags)) {
+		netif_addr_unlock_bh(dev);
+		return;
+	}
+	netif_addr_unlock_bh(dev);
+
+	spin_lock_irq(&priv->lock);
+	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags))
+		goto out;
+
+	if (!priv->broadcast) {
+		struct ipoib_mcast *broadcast;
+
+		broadcast = ipoib_mcast_alloc(dev, 0);
+		if (!broadcast) {
+			ipoib_warn(priv, "failed to allocate broadcast group\n");
+			/*
+			 * Restart us after a 1 second delay to retry
+			 * creating our broadcast group and attaching to
+			 * it.  Until this succeeds, this ipoib dev is
+			 * completely stalled (multicast wise).
+			 */
+			__ipoib_mcast_schedule_join_thread(priv, NULL, 1);
+			goto out;
+		}
+
+		memcpy(broadcast->mcmember.mgid.raw, priv->dev->broadcast + 4,
+		       sizeof (union ib_gid));
+		priv->broadcast = broadcast;
+
+		__ipoib_mcast_add(dev, priv->broadcast);
+	}
+
+	if (!test_bit(IPOIB_MCAST_FLAG_ATTACHED, &priv->broadcast->flags)) {
+		if (IS_ERR_OR_NULL(priv->broadcast->mc) &&
+		    !test_bit(IPOIB_MCAST_FLAG_BUSY, &priv->broadcast->flags)) {
+			mcast = priv->broadcast;
+			if (mcast->backoff > 1 &&
+			    time_before(jiffies, mcast->delay_until)) {
+				delay_until = mcast->delay_until;
+				mcast = NULL;
+			}
+		}
+		goto out;
+	}
+
+	/*
+	 * We'll never get here until the broadcast group is both allocated
+	 * and attached
+	 */
+	list_for_each_entry(mcast, &priv->multicast_list, list) {
+		if (IS_ERR_OR_NULL(mcast->mc) &&
+		    !test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags) &&
+		    (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) ||
+		     !skb_queue_empty(&mcast->pkt_queue))) {
+			if (mcast->backoff == 1 ||
+			    time_after_eq(jiffies, mcast->delay_until)) {
+				/* Found the next unjoined group */
+				if (ipoib_mcast_join(dev, mcast)) {
+					spin_unlock_irq(&priv->lock);
+					return;
+				}
+			} else if (!delay_until ||
+				 time_before(mcast->delay_until, delay_until))
+				delay_until = mcast->delay_until;
+		}
+	}
+
+	mcast = NULL;
+	ipoib_dbg_mcast(priv, "successfully started all multicast joins\n");
+
+out:
+	if (delay_until) {
+		cancel_delayed_work(&priv->mcast_task);
+		queue_delayed_work(priv->wq, &priv->mcast_task,
+				   delay_until - jiffies);
+	}
+	if (mcast)
+		ipoib_mcast_join(dev, mcast);
+
+	spin_unlock_irq(&priv->lock);
+}
+
+void ipoib_mcast_start_thread(struct net_device *dev)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	unsigned long flags;
+
+	ipoib_dbg_mcast(priv, "starting multicast thread\n");
+
+	spin_lock_irqsave(&priv->lock, flags);
+	__ipoib_mcast_schedule_join_thread(priv, NULL, 0);
+	spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+int ipoib_mcast_stop_thread(struct net_device *dev)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+
+	ipoib_dbg_mcast(priv, "stopping multicast thread\n");
+
+	cancel_delayed_work_sync(&priv->mcast_task);
+
+	return 0;
+}
+
+static int ipoib_mcast_leave(struct net_device *dev, struct ipoib_mcast *mcast)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	struct rdma_netdev *rn = netdev_priv(dev);
+	int ret = 0;
+
+	if (test_and_clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags))
+		ipoib_warn(priv, "ipoib_mcast_leave on an in-flight join\n");
+
+	if (!IS_ERR_OR_NULL(mcast->mc))
+		ib_sa_free_multicast(mcast->mc);
+
+	if (test_and_clear_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags)) {
+		ipoib_dbg_mcast(priv, "leaving MGID %pI6\n",
+				mcast->mcmember.mgid.raw);
+
+		/* Remove ourselves from the multicast group */
+		ret = rn->detach_mcast(dev, priv->ca, &mcast->mcmember.mgid,
+				       be16_to_cpu(mcast->mcmember.mlid));
+		if (ret)
+			ipoib_warn(priv, "ib_detach_mcast failed (result = %d)\n", ret);
+	} else if (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags))
+		ipoib_dbg(priv, "leaving with no mcmember but not a "
+			  "SENDONLY join\n");
+
+	return 0;
+}
+
+/*
+ * Check if the multicast group is sendonly. If so remove it from the maps
+ * and add to the remove list
+ */
+void ipoib_check_and_add_mcast_sendonly(struct ipoib_dev_priv *priv, u8 *mgid,
+				struct list_head *remove_list)
+{
+	/* Is this multicast ? */
+	if (*mgid == 0xff) {
+		struct ipoib_mcast *mcast = __ipoib_mcast_find(priv->dev, mgid);
+
+		if (mcast && test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
+			list_del(&mcast->list);
+			rb_erase(&mcast->rb_node, &priv->multicast_tree);
+			list_add_tail(&mcast->list, remove_list);
+		}
+	}
+}
+
+void ipoib_mcast_remove_list(struct list_head *remove_list)
+{
+	struct ipoib_mcast *mcast, *tmcast;
+
+	/*
+	 * make sure the in-flight joins have finished before we attempt
+	 * to leave
+	 */
+	list_for_each_entry_safe(mcast, tmcast, remove_list, list)
+		if (test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags))
+			wait_for_completion(&mcast->done);
+
+	list_for_each_entry_safe(mcast, tmcast, remove_list, list) {
+		ipoib_mcast_leave(mcast->dev, mcast);
+		ipoib_mcast_free(mcast);
+	}
+}
+
+void ipoib_mcast_send(struct net_device *dev, u8 *daddr, struct sk_buff *skb)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	struct rdma_netdev *rn = netdev_priv(dev);
+	struct ipoib_mcast *mcast;
+	unsigned long flags;
+	void *mgid = daddr + 4;
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)		||
+	    !priv->broadcast					||
+	    !test_bit(IPOIB_MCAST_FLAG_ATTACHED, &priv->broadcast->flags)) {
+		++dev->stats.tx_dropped;
+		dev_kfree_skb_any(skb);
+		goto unlock;
+	}
+
+	mcast = __ipoib_mcast_find(dev, mgid);
+	if (!mcast || !mcast->ah) {
+		if (!mcast) {
+			/* Let's create a new send only group now */
+			ipoib_dbg_mcast(priv, "setting up send only multicast group for %pI6\n",
+					mgid);
+
+			mcast = ipoib_mcast_alloc(dev, 0);
+			if (!mcast) {
+				ipoib_warn(priv, "unable to allocate memory "
+					   "for multicast structure\n");
+				++dev->stats.tx_dropped;
+				dev_kfree_skb_any(skb);
+				goto unlock;
+			}
+
+			set_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags);
+			memcpy(mcast->mcmember.mgid.raw, mgid,
+			       sizeof (union ib_gid));
+			__ipoib_mcast_add(dev, mcast);
+			list_add_tail(&mcast->list, &priv->multicast_list);
+		}
+		if (skb_queue_len(&mcast->pkt_queue) < IPOIB_MAX_MCAST_QUEUE) {
+			/* put pseudoheader back on for next time */
+			skb_push(skb, sizeof(struct ipoib_pseudo_header));
+			skb_queue_tail(&mcast->pkt_queue, skb);
+		} else {
+			++dev->stats.tx_dropped;
+			dev_kfree_skb_any(skb);
+		}
+		if (!test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags)) {
+			__ipoib_mcast_schedule_join_thread(priv, NULL, 0);
+		}
+	} else {
+		struct ipoib_neigh *neigh;
+
+		spin_unlock_irqrestore(&priv->lock, flags);
+		neigh = ipoib_neigh_get(dev, daddr);
+		spin_lock_irqsave(&priv->lock, flags);
+		if (!neigh) {
+			neigh = ipoib_neigh_alloc(daddr, dev);
+			/* Make sure that the neigh will be added only
+			 * once to mcast list.
+			 */
+			if (neigh && list_empty(&neigh->list)) {
+				kref_get(&mcast->ah->ref);
+				neigh->ah	= mcast->ah;
+				neigh->ah->valid = 1;
+				list_add_tail(&neigh->list, &mcast->neigh_list);
+			}
+		}
+		spin_unlock_irqrestore(&priv->lock, flags);
+		mcast->ah->last_send = rn->send(dev, skb, mcast->ah->ah,
+						IB_MULTICAST_QPN);
+		if (neigh)
+			ipoib_neigh_put(neigh);
+		return;
+	}
+
+unlock:
+	spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+void ipoib_mcast_dev_flush(struct net_device *dev)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(dev);
+	LIST_HEAD(remove_list);
+	struct ipoib_mcast *mcast, *tmcast;
+	unsigned long flags;
+
+	mutex_lock(&priv->mcast_mutex);
+	ipoib_dbg_mcast(priv, "flushing multicast list\n");
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	list_for_each_entry_safe(mcast, tmcast, &priv->multicast_list, list) {
+		list_del(&mcast->list);
+		rb_erase(&mcast->rb_node, &priv->multicast_tree);
+		list_add_tail(&mcast->list, &remove_list);
+	}
+
+	if (priv->broadcast) {
+		rb_erase(&priv->broadcast->rb_node, &priv->multicast_tree);
+		list_add_tail(&priv->broadcast->list, &remove_list);
+		priv->broadcast = NULL;
+	}
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	ipoib_mcast_remove_list(&remove_list);
+	mutex_unlock(&priv->mcast_mutex);
+}
+
+static int ipoib_mcast_addr_is_valid(const u8 *addr, const u8 *broadcast)
+{
+	/* reserved QPN, prefix, scope */
+	if (memcmp(addr, broadcast, 6))
+		return 0;
+	/* signature lower, pkey */
+	if (memcmp(addr + 7, broadcast + 7, 3))
+		return 0;
+	return 1;
+}
+
+void ipoib_mcast_restart_task(struct work_struct *work)
+{
+	struct ipoib_dev_priv *priv =
+		container_of(work, struct ipoib_dev_priv, restart_task);
+	struct net_device *dev = priv->dev;
+	struct netdev_hw_addr *ha;
+	struct ipoib_mcast *mcast, *tmcast;
+	LIST_HEAD(remove_list);
+	struct ib_sa_mcmember_rec rec;
+
+	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags))
+		/*
+		 * shortcut...on shutdown flush is called next, just
+		 * let it do all the work
+		 */
+		return;
+
+	ipoib_dbg_mcast(priv, "restarting multicast task\n");
+
+	netif_addr_lock_bh(dev);
+	spin_lock_irq(&priv->lock);
+
+	/*
+	 * Unfortunately, the networking core only gives us a list of all of
+	 * the multicast hardware addresses. We need to figure out which ones
+	 * are new and which ones have been removed
+	 */
+
+	/* Clear out the found flag */
+	list_for_each_entry(mcast, &priv->multicast_list, list)
+		clear_bit(IPOIB_MCAST_FLAG_FOUND, &mcast->flags);
+
+	/* Mark all of the entries that are found or don't exist */
+	netdev_for_each_mc_addr(ha, dev) {
+		union ib_gid mgid;
+
+		if (!ipoib_mcast_addr_is_valid(ha->addr, dev->broadcast))
+			continue;
+
+		memcpy(mgid.raw, ha->addr + 4, sizeof(mgid));
+
+		mcast = __ipoib_mcast_find(dev, &mgid);
+		if (!mcast || test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
+			struct ipoib_mcast *nmcast;
+
+			/* ignore group which is directly joined by userspace */
+			if (test_bit(IPOIB_FLAG_UMCAST, &priv->flags) &&
+			    !ib_sa_get_mcmember_rec(priv->ca, priv->port, &mgid, &rec)) {
+				ipoib_dbg_mcast(priv, "ignoring multicast entry for mgid %pI6\n",
+						mgid.raw);
+				continue;
+			}
+
+			/* Not found or send-only group, let's add a new entry */
+			ipoib_dbg_mcast(priv, "adding multicast entry for mgid %pI6\n",
+					mgid.raw);
+
+			nmcast = ipoib_mcast_alloc(dev, 0);
+			if (!nmcast) {
+				ipoib_warn(priv, "unable to allocate memory for multicast structure\n");
+				continue;
+			}
+
+			set_bit(IPOIB_MCAST_FLAG_FOUND, &nmcast->flags);
+
+			nmcast->mcmember.mgid = mgid;
+
+			if (mcast) {
+				/* Destroy the send only entry */
+				list_move_tail(&mcast->list, &remove_list);
+
+				rb_replace_node(&mcast->rb_node,
+						&nmcast->rb_node,
+						&priv->multicast_tree);
+			} else
+				__ipoib_mcast_add(dev, nmcast);
+
+			list_add_tail(&nmcast->list, &priv->multicast_list);
+		}
+
+		if (mcast)
+			set_bit(IPOIB_MCAST_FLAG_FOUND, &mcast->flags);
+	}
+
+	/* Remove all of the entries don't exist anymore */
+	list_for_each_entry_safe(mcast, tmcast, &priv->multicast_list, list) {
+		if (!test_bit(IPOIB_MCAST_FLAG_FOUND, &mcast->flags) &&
+		    !test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
+			ipoib_dbg_mcast(priv, "deleting multicast group %pI6\n",
+					mcast->mcmember.mgid.raw);
+
+			rb_erase(&mcast->rb_node, &priv->multicast_tree);
+
+			/* Move to the remove list */
+			list_move_tail(&mcast->list, &remove_list);
+		}
+	}
+
+	spin_unlock_irq(&priv->lock);
+	netif_addr_unlock_bh(dev);
+
+	ipoib_mcast_remove_list(&remove_list);
+
+	/*
+	 * Double check that we are still up
+	 */
+	if (test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)) {
+		spin_lock_irq(&priv->lock);
+		__ipoib_mcast_schedule_join_thread(priv, NULL, 0);
+		spin_unlock_irq(&priv->lock);
+	}
+}
+
+#ifdef CONFIG_INFINIBAND_IPOIB_DEBUG
+
+struct ipoib_mcast_iter *ipoib_mcast_iter_init(struct net_device *dev)
+{
+	struct ipoib_mcast_iter *iter;
+
+	iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+	if (!iter)
+		return NULL;
+
+	iter->dev = dev;
+	memset(iter->mgid.raw, 0, 16);
+
+	if (ipoib_mcast_iter_next(iter)) {
+		kfree(iter);
+		return NULL;
+	}
+
+	return iter;
+}
+
+int ipoib_mcast_iter_next(struct ipoib_mcast_iter *iter)
+{
+	struct ipoib_dev_priv *priv = ipoib_priv(iter->dev);
+	struct rb_node *n;
+	struct ipoib_mcast *mcast;
+	int ret = 1;
+
+	spin_lock_irq(&priv->lock);
+
+	n = rb_first(&priv->multicast_tree);
+
+	while (n) {
+		mcast = rb_entry(n, struct ipoib_mcast, rb_node);
+
+		if (memcmp(iter->mgid.raw, mcast->mcmember.mgid.raw,
+			   sizeof (union ib_gid)) < 0) {
+			iter->mgid      = mcast->mcmember.mgid;
+			iter->created   = mcast->created;
+			iter->queuelen  = skb_queue_len(&mcast->pkt_queue);
+			iter->complete  = !!mcast->ah;
+			iter->send_only = !!(mcast->flags & (1 << IPOIB_MCAST_FLAG_SENDONLY));
+
+			ret = 0;
+
+			break;
+		}
+
+		n = rb_next(n);
+	}
+
+	spin_unlock_irq(&priv->lock);
+
+	return ret;
+}
+
+void ipoib_mcast_iter_read(struct ipoib_mcast_iter *iter,
+			   union ib_gid *mgid,
+			   unsigned long *created,
+			   unsigned int *queuelen,
+			   unsigned int *complete,
+			   unsigned int *send_only)
+{
+	*mgid      = iter->mgid;
+	*created   = iter->created;
+	*queuelen  = iter->queuelen;
+	*complete  = iter->complete;
+	*send_only = iter->send_only;
+}
+
+#endif /* CONFIG_INFINIBAND_IPOIB_DEBUG */